From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757779AbZEABBQ (ORCPT ); Thu, 30 Apr 2009 21:01:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752799AbZEABBA (ORCPT ); Thu, 30 Apr 2009 21:01:00 -0400 Received: from mx2.redhat.com ([66.187.237.31]:35131 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750799AbZEABA7 (ORCPT ); Thu, 30 Apr 2009 21:00:59 -0400 Date: Thu, 30 Apr 2009 20:59:36 -0400 From: Rik van Riel To: Andrew Morton Cc: Elladan , peterz@infradead.org, linux-kernel@vger.kernel.org, tytso@mit.edu, kosaki.motohiro@jp.fujitsu.com, linux-mm@kvack.org Subject: Re: [PATCH] vmscan: evict use-once pages first (v2) Message-ID: <20090430205936.0f8b29fc@riellaptop.surriel.com> In-Reply-To: <20090430174536.d0f438dd.akpm@linux-foundation.org> References: <20090428044426.GA5035@eskimo.com> <20090428192907.556f3a34@bree.surriel.com> <1240987349.4512.18.camel@laptop> <20090429114708.66114c03@cuia.bos.redhat.com> <20090430072057.GA4663@eskimo.com> <20090430174536.d0f438dd.akpm@linux-foundation.org> Organization: Red Hat, Inc Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 30 Apr 2009 17:45:36 -0700 Andrew Morton wrote: > Were you able to tell whether altering /proc/sys/vm/swappiness > appropriately regulated the rate at which the mapped page count > decreased? That should not make a difference at all for mapped file pages, after the change was merged that makes the VM ignores the referenced bit of mapped active file pages. Ever since the split LRU code was merged, all that the swappiness controls is the aggressiveness of file vs anonymous LRU scanning. Currently the kernel has no effective code to protect the page cache working set from streaming IO. Elladan's bug report shows that we do need some kind of protection... -- All rights reversed. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail143.messagelabs.com (mail143.messagelabs.com [216.82.254.35]) by kanga.kvack.org (Postfix) with SMTP id 134B76B003D for ; Thu, 30 Apr 2009 21:00:20 -0400 (EDT) Date: Thu, 30 Apr 2009 20:59:36 -0400 From: Rik van Riel Subject: Re: [PATCH] vmscan: evict use-once pages first (v2) Message-ID: <20090430205936.0f8b29fc@riellaptop.surriel.com> In-Reply-To: <20090430174536.d0f438dd.akpm@linux-foundation.org> References: <20090428044426.GA5035@eskimo.com> <20090428192907.556f3a34@bree.surriel.com> <1240987349.4512.18.camel@laptop> <20090429114708.66114c03@cuia.bos.redhat.com> <20090430072057.GA4663@eskimo.com> <20090430174536.d0f438dd.akpm@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Andrew Morton Cc: Elladan , peterz@infradead.org, linux-kernel@vger.kernel.org, tytso@mit.edu, kosaki.motohiro@jp.fujitsu.com, linux-mm@kvack.org List-ID: On Thu, 30 Apr 2009 17:45:36 -0700 Andrew Morton wrote: > Were you able to tell whether altering /proc/sys/vm/swappiness > appropriately regulated the rate at which the mapped page count > decreased? That should not make a difference at all for mapped file pages, after the change was merged that makes the VM ignores the referenced bit of mapped active file pages. Ever since the split LRU code was merged, all that the swappiness controls is the aggressiveness of file vs anonymous LRU scanning. Currently the kernel has no effective code to protect the page cache working set from streaming IO. Elladan's bug report shows that we do need some kind of protection... -- All rights reversed. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org